460 FORD w/tunnel ram 750's or single 850???

[76Tahiti460]

I am almost finshed gathering all my quality parts for my 460 FBB build-up, minus the pistons (compression???) and intake/carb set-up. I have heard alot of hype about tunnel rams and single carb set-ups, but everyone has there opinion. Tunnel rams are just damm good looking on a 18 foot jetboat when polished and set-up right, but nothing looks worse than not being able to start it, or having to bottle feed it at the peir (Major fire hazard). Now are the unreliable set-ups people are referring to set-up correctly? IE flowmatched carbs, enough fuel pressure, quality linkage sets (not cheap!!), respectable compression ratios, enough battery to turn it over LOL, etc, etc... Yeah I would love to tear the river up with a single carb and performer RPM set-up, but why can't I do it with a tunnel ram that is set-up correctly and dependable? Could some one give me some sound advice to how I should go about setting this up on my boat so I am ready for next memorial weekend. My planned expenses are leaning towards (460 BB bored 0.060+) a polished Weiand Tunnel Ram, twin flowmatched identically jetted 750 D.pumper carbs w/barry grant linkage, the boat has a holley blue pump with regulator (is this enough pump for this set-up?). The bottom end is stock (externally balanced) ARP fastners, heads are 92cc heads (cheap heads) roller rockers (modified to work w/heads) Comp cams Extreme marine cam matched to HP/torque band, stiffer springs matched to cam lift. I am taking my time to do this right because I want this awesome looking and performing set-up but I want it done right. I think I have my homework done throughly, but if I left something please inform me!!! PLEASE READ THIS ALL CAREFULLY AND LIST SOME SOUND ADVICE WITH PART NUMBERS IF POSSIABLE... I am attempting to get this TOPIC as popular as the "Berk" topic but with a little less BS...Let the replys begin

[NordicSquirt]

Sounds like you have weighed ALL of your options, but you are letting the "Looks" factor overrun the "Run" factor. My boat has a 454, which HAD a Tunnel Ram and two List# 1850 Holley 600 cfm Vac. Secondary carbs. After much trouble with linkages, fuel delivery problems,idling problems,etc. They were removed in favor of a Holley Single Plane Intake, which is called a "Strip Dominator" and an 850 DP Holley. With this setup there are no linkages to fabricate or purchase, less fuel problems, easier starting, etc. Another factor you didn't consider was fuel consumption. After switching from the TR, I am now using a lot LESS fuel, and it starts on the first try. I will agree that a polished TR with Scoop, etc. looks impressive, but performance is not always at its best with a TR. Personally, I lost no HP or RPM when I removed my setup. I installed a new cam and headers at that time and picked up about 500 rpm. It's strictly a personal preference, but for me I choose performance over looks. Good luck with your decision.

[76Tahiti460]

Ok I understand the dependability of the single carb set-up and the fact there is less complications with parts. But was your tunnel ram set-up with quality parts? I understand that cost sometimes supercedes ones wants, but if your Tunnel Ram was set-up with quality parts such as flow matched carbs, well engineered linkage, sufficent fuel pressure and volume, do you think that your set-up could have been just as fesiable as your single carb set-up minus the cost? We both know that the tunnel ram runs and performs better in the higher RPM applications and is inherently rough at idle compared to a single set-up and the single carb set-up is a off the line choice up to about 5-6K RPM, but if the cam complimented the tunnel ram as well as compression ratio, do you think that cost would be the only factor in a reliable tunnel ram verse single carb set-up, or do you think that no one yet (Barry Grant, Weiand, Holley) has come up with a available system yet that would cure your past tunnel ram problems? If they have a kit for linkage that is unparelell to any other, than I will save for it. As you can tell I believe in performance as much as looks, but lets face it....the river is more image than performance...no? But how long will I put up with image (tunnel ram unrelibility) before I wish I had listened to you about a single carb 850 Demon or so and dual plane? I am not trying to beat a dead horse, I see your opinion, but I am trying to better understand what I want and how I can get there at what cost.

[Oldsquirt]

Plenty of guys run tunnel rams with 2-fours, some for speed , some for looks. Done right you shouldn't have any problems. The only part of your plan that worries me is that the carb choice is way too big for the engine. You will never turn that motor high enough to require 1500cfm! Think along the lines of 2-600's or even smaller. It will make for a more drivable set up. Good luck.

[76Tahiti460]

Here are two carbs that I was looking at purchaseing off ebay, what do you think about these, and also would my Holley Blue pump with 6AN line supply sufficent fuel to my beast?
matched pair of 600 CFM Holley Vacuum Secondary Carbs
List 1850. These carbs have been professionally rebuilt and are ready to
bolt on and go. This is a very clean set of carbs and will look nice on your
dual quad manifold. The carbs have #66 jets, #65 power valve, and #9
metering plates stock. Along with the new kit the carbs have new vacuum
secondary diaphragms installed. They also have power valve blowout
protection check valves installed, a must for 2x4 dual quad set ups and
something many rebuilders don't take the time to do. I guarantee these
carburetors for a period of 6 months or I will repair/replace or refund the
carb for the full purchase price, so please bid with confidance. If you have
any questions please ask and I will answer asap. Payment: money orders
accepted. Buyer to pay actual shipping charges.

[76Tahiti460]

Do I interpret the word "Matched carbs" as same jets, metering blocks, etc....or can I safely assume they are flowmatched as well? He wants $280.00 for both, "I said both!" one money order for $280.00 delivered to me in San Diego. Yeah or ney?
[This message has been edited by 76Tahiti460 (edited August 21, 2001).]

[Brendella]

I have a tunnel ram with dual 750's thats the way I bought the boat. don't know about the jets, but mine runs real good except for first time start ups. takes alittle gas to get down the TR. I believe that with the TR you will launch alot faster. Atleast I do compare to my buddies who run singles. If the price is right I will sell mine as one unit. tunnel ram carbs and scoop. the only thing is my Tr is not pollished.

[jroos]

I say yeah Tahiti! I`m doing the same thing, but with 750`s. 4150 series and 2 inch spacers for more height. I`m doing this because i already have a 750 and a tunnel looks a whole hell of a lot better than a single carb. I`m not worried about fuel, as long as I`m not spittin` raw fuel out the pipes. A 600 new goes for about 180-200. This guy may be pulling your leg about what`s in them. Ask some questions about general automotives and see what his answers are. Some say I will gain my ass of and others say I will lose, others say its too damn much carb(1500cfm). Only thing that has me skeptical is the fact that I`m running exhaust logs and I know that`ll hurt my max rpm. If you look in the new Hot Boat jet tech, the article, continued on pg. 122, states that a tunnel w/ 750`s gained. And that a jet is hard to over carb. I just don`t want to sacrifice idle quality or dependebility. Basically, I`m gonna gamble. If it doesn`t work to my liking, I`ll go 600`s. 750`s are way easier to unload than 600`s.

[racingrascal]

Brendella, if it runs so good whys sell the set up? Just wondering, I am putting a tunnel ram on my new boat. I all ready have the parts though,or should I say the builder does.
Andy

[76Tahiti460]

So the tunnel ram is a no brainer part # wise, but what about linkage (inline for 1850's, or transverse/sideways for 750's), and what kind of fuel set-up are you guys running? Electric or mechanical?